1. Field of the Invention
The present invention relates to a mineral absorption promoting agent, and in particular to a mineral absorption promoting agent containing oligouronic acid degree of polymerization (n)=1 to 9!, which promotes absorption of minerals such as iron, calcium, etc. into living organisms.
2. Description of the Prior Art
In recent years, it has become increasingly difficult to take minerals from foods because of propagation of refined and sophisticated food products, meals with imbalanced nutrition and irregular eating habits. For this reason, in order to supply constituents or activators of numerous enzyme systems, which are essential elements such as calcium, magnesium, potassium, zinc, manganese, copper, iron, etc. indispensable for the normal function of living organisms, it has been proposed to utilize complexes or conjugates of these essential elements.
For example, chondroitin sulfate-iron(II)-iron(III), algin-iron(II)-iron(III), and pectin-iron(II)-iron(III) have been reported as such substances Japanese Patent Examined Publication No. 44-2802, Yakugaku Zasshi (Journal of Pharmaceutical Science), 90, 120-126 (1970); Yakugaku Zasshi (Journal of Pharmaceutical Science), 90, 1480-1487 (1970); Chemical Abstract, 60, 5287 f.; Belgian Patent Specifications Nos. 619,267 and 652,508!. Metal ion complexes of oligogalacturonic acids or polygalacturonic acids also have been reported as such substances (Japanese Patent Examined Publication No. 59-42683).
Since the above complexes or conjugates of algin-iron(II)-iron(III), pectin-iron(II)-iron(III) and degraded casein-iron(II)-iron(III) are chemically undefined, the metal complexes which have reproducible quality and reproducible biological effects are not obtainable.
Though metal ion complexes of oligogalacturonic acid or polygalacturonic acid have reproducible quality and reproducible biological effects, they are relatively macromolecular substances with polymerization degree (n) of 10 to 145, and are not easily absorbed into living organisms.
In particular, the deficiency of iron or calcium may cause anemia or osteoporosis, and there are now strong demands for foodstuffs and medical drug preparations which can be ingested efficiently.